1. Field of the Invention
The present invention relates to an engine mount of an aircraft including a turbofan type engine, and the aircraft.
2. Description of the Related Art
A turbofan type engine of an aircraft is mounted to a wing via a structural member called a pylon strut (see, for example, FIG. 13.4.3 of “Airframe structural design second edition” by Micheal C. Y. Niu, Hong Kong Conmilit Press LTD pp. 482 to 483).
As shown in FIG. 4, a pylon strut 1 is provided at an undersurface of a wing 2 to extend toward a front in a flying direction. In an engine 4, a fan section 4a at the front is mounted to an undersurface of the pylon strut 1 by a front engine mount 5, and a core section 4b at the rear is mounted to the undersurface of the pylon strut 1 by a rear engine mount 6.
Forces in various directions work between a side of the engine 4 and a side of the pylon strut 1. For example, by the thrust force of the engine 4, and the force at the time of reverse thrust, the force in a longitudinal direction works. Further, at the time of landing, the force in a vertical direction works. As the force in the vertical direction, impacts and the like can be cited, which occur at the time of, for example, hard landing (landing accompanied by the impact in the vertical direction), and at the time of belly landing. Further, at the time of operation of the engine 4, torque in the rotating direction by rotation of the fan also works. Therefore, the front engine mount 5 and the rear engine mount 6 need to have sufficient strength against these forces.
In recent years, the engine 4 with a high bypass ratio has been developed, in which the diameter of the fan section 4a is large with respect to the diameter of the core section 4b. In the engine 4 with such a high bypass ratio, the space between the core section 4b and the pylon strut 1 is increased in the rear part of the engine 4. With this, the rear engine mount 6 becomes large in length (becomes large in height).
However, if the rear engine mount 6 becomes large in length, the moment of the force which works between the side of the engine 4 and the side of the pylon strut 1 becomes large. As a result, in order to secure the strength of the rear engine mount 6, the rear engine mount 6 has to be made thick or the like, and this leads to an increase in weight.
Further, the front engine mount 5 and the rear engine mount 6 are provided in a nacelle 7 which forms the outer shell of the engine 4. In the nacelle 7, various devices are housed especially above the core section 4b of the engine 4. If the rear engine mount 6 becomes large in length, the housing space for these devices becomes small, and there is also room for improvement from the viewpoint of effective use of the space.